401 Rear Main Seal

**57Special** · 04-04-2015, 03:53 PM

I have a freshly rebuilt 401 with a rear main seal leak. Unfortunately a neoprene or Viton seal was not used. I have pulled the engine and want to install rubber seal . Can someone direct me to a supplier for the rubber seal Also; Is there machining required for the rubber seals? Thanks

**telriv** · 04-04-2015, 05:50 PM

The seal I sell requires NO mods. A bolt-in swap. I also send the sealer I normally use & directions. While you have it apart how about the front seal??? I have those also. ALL in stock!!!

Tom T.

**buickrodder** · 04-05-2015, 03:38 PM

We find that sometimes the seals need to be clipped to fit properly. I pioneered the rubber crank seal back in 82 (as far as I know). If the builder used a rope seal he also must have used Felpro gaskets and head gaskets leak oil with them. Read the tech info in my website nailheadbuick.com . Russ.

**telriv** · 04-05-2015, 05:30 PM

I have an easy fix if the gasket is weeping oil WITHOUT pulling heads or replacing gaskets.

**57Special** · 04-05-2015, 07:44 PM

Thanks for your comments. The engine builder did use a rope seal and the head gaskets are weeping. I will definitely follow-up on the rubber seals. Could you expand on the fix for the head gaskets leaking oil or should I contact you directly?

**telriv** · 04-06-2015, 07:10 AM

Best to give me a call. If I'm not around leave a message & the best time to call. If the answering machine is full I DO have caller I.D. so I can return the call. I don't know where you live. I'm in Ct. EST.

Tom T.

**mr62buick** · 04-23-2015, 05:34 PM

They are the same as a 425 Cadillac motor. Just tell they guy... sheesh

**telriv** · 04-24-2015, 06:46 AM

Have NOT received a call as of yet that I know of.

**57Special** · 04-24-2015, 08:35 AM

I did speak with both posters that had suggested fixes. The information provided was helpful. I found an engine shop in my area that was familiar with the nailheads and took the time to learn more from information that I received plus some research of his own. In this case the slinger rings had been machined off the crankshaft at some point in the engines history. The rope seal that was installed didn't have a chance of working properly without them plus thereas an installation issue with the rope seal installation. A 2 piece neoprene seal was installed, don't know the result yet but it should work..

**buickrodder** · 04-24-2015, 09:17 AM

Slinger rings? if you are talking about grooves cut in a spiral on the seal surface of the crank? Nailhead's don't have them. That is something Ford and some others have used.. I am adding more tech info about installing rubber seals in my website plus info with the seal that is specific to the Nailhead. Yes you can buy seals used in other engines but without the correct info and a good quality seal you may not have a happy ending. I have added lots of tech info in the last 2 years, I have so much BS advice that people get on line about Nailhead's from incorrect torque spec's, cam's recommend than don't work, parts swapping and using too small of carbs.. etc I want Nailhead loves to have a place to go that has correct info from my many years of experience. The last thing we want is for someone to get flustrated and use a chevy! I think I have stopped many chevy engine swaps..